The invention proceeds from a battery cell having a metallic housing. The subject matter of the present invention is also a method for producing a battery cell of this type. Furthermore, the invention relates to a battery having a battery cell of this type.
It is known from the prior art that batteries, such as, in particular, lithium-ion batteries, consist at least of a battery module or advantageously also of a plurality of battery modules. Furthermore, a battery module additionally preferably has a multiplicity of individual battery cells which are connected among one another to form the battery module. To this end, the individual battery cells in each case have a positive and a negative voltage tap and are connected to one another in series or parallel by means of cell connectors. The capacity and/or current strength of the battery module is increased in the case of a parallel connection of the individual battery cells to one another, whereas the voltage of the battery module is increased in the case of a serial connection of the individual battery cells to one another.
Here, the positive and negative voltage tap of an individual battery cell is arranged on an outer side of the housing of the battery cell, which outer side is adjacent with respect to a surrounding area, and is additionally connected electrically to a positive and negative pole, respectively, of an electrode assembly which is received in an interior of the battery cell. As a result, the energy density of a battery module which can be realized is reduced on account of the installation space which is required by the voltage taps and their connection by means of cell connectors.
The prior art, for example DE 10 2011 076 919 A1, has disclosed a battery cell having a housing with at least one electrode assembly which is arranged in the housing. Here, the housing has two housing elements which substantially separate the electrode assembly from the surrounding area. A first housing element is connected electrically to a positive pole of the electrode assembly, and a second housing element is connected electrically to a negative pole of the electrode assembly. Furthermore, an insulation element is arranged between the first housing element and the second housing element. Therefore, the battery cell can be contacted electrically on the first housing element and on the second housing element, as a result of which the energy density which can be realized can be increased by way of an omission of separate voltage taps which are arranged on an outer side of the housing, which outer side is adjacent with respect to the surrounding area.
The battery cell and the method of the invention have the advantage that at least one insulation element which is arranged between a first housing element and a second housing element of the metallic housing for electric insulation has at least one barrier layer, and the at least one barrier layer reduces, in particular, a diffusion of solvent of the electrolyte and of moisture through the insulation element. As a result, an electrode assembly which is received in the interior of the metallic housing can be protected, in particular, in an improved manner against influences from the surrounding area of the battery cell in comparison with battery cells which are known from the prior art.